Simulated stone product and method of forming same



Unite States Patent-O SIMULATED STONE PRODUCT AND METHOD I OF FORMINGSAME Thomas M. Fox, 1050 th St., Santa Monica, Calif.

Filed Nov. 24, 1958, Ser. No. 775,983

'3 Claims. k(Cl. 117-7-9)V This invention generally relates to a methodof forming and composition for a simulated stone product. Moreparticularly, the invention concerns an artificial plastic stone whichhas primary application in conjunction with home and oliice interiorsalthough the product of the present invention may also be applied underother conditions, for vexample, in protected areas of exteriorlandscaping or the like.

It is apparent that natural stone and rock materials, althoughloftentimes used functionally for fireplaces and the like, alsol'serve adecorative purpose to form-a part of the interior design of homes andofhces. Such materials are usually formed into a solid wall by means ofabonding of cementitious composition. It will brerappreciatedfhowever,that rocksvand stones, because of their weight andV bulkiness arelsometimes diflicultto conveniently transport to the job site as well asto assemble and position during the construction process. Furthermore,such stone and rock materials are oftentimes not available in thequantity and size desired in areas near the building construction andconsiderable expense may be required to procure these materials.

It is, therefore, an object of the present invention to provide acomposition for and a method of forming a simulated stone or rock-likematerial, which is relatively light in weight, and which may be readilymanufactured at economical price levels.

Another object of 'the present invention is to provide a composition forforming a simulated stone and rocklike product which will yield theappearance of natural stone and yet which embodies a composition ofmaterials requiring a relatively simple manufacturing process.

Still another object of the present invention is to provide la methodand composition for a simulated stone or rock-like product, which ifdesired, may be completely formed by painters or other tradesmen at thesite of the building construction at the time the interior finishingwork is being completed.

These and other objects land advantages of the present invention aregenerally achieved by providing a composition for a simulated stone orrock product consisting of a foamed plastic substance having coatedthereover a paint material layer. The paint layer has imbedded thereinsand particles to yield the appearance of a natural stone surface. Ofcourse, a paint is used which has a stone or rock-like color so as tosimulate as closely as possible the natural surface coloring of stoneand rock materials.

A preferred method of making the simulated stone or rock product of thepresent invention comprises the step of first subjecting an exteriorportion or surface area of a foamed plastic material to a given pressureto impress therein an irregular contour characterized by lands andgrooves of different shapes. For this purpose, the plastic material isof a type which necessarily will set in its deformed shape whensubjected to a given pressure. Thereafter, once the irregular contourhas been formed,

Patented Sept. 20, 1960 the layer of paint is coated over the exteriorportion either by brush or spray methods or the like. While the paint isstill in a wet condition, sand particles are sprayed or otherwisedeposited upon the paint to become imbedded in the paint layer and cellsof the plastic material to thereby form a simulated stone or rock appearance upon drying of the paint.

A better understanding of the present invention will be had by referenceto the drawings merely illustrating schematically an improved method andcomposition for the simulated stone or rock material of thepresent-invention, and wherein:

Figure 1 is a schematic representation of the pressure contour-ing ofthe surface of a foamed plastic sheet material as the rst step of themethod of the present invention;

Figure 2 is a view of the foamed plastic sheet after application of apaint layer thereto; and

Figure 3 is a sectional view of the plasticl sheet in completed formwith the sand particles imbedded in the dried paint layer. v p

Referring now to Figure l, there are shown a pair of spaced rollers 10and 11 adaptedto be drivenin op# posing directions #as indicated by thearrows. Roller 10 is drivingly mounted on a shaftlZ; similarly, roller11 is drivingly mounted on a shaft-13. The rollers 10 and 11 may bedriven through their respective shafts by any conventional drivingmeans, for example, geared motors or the like. Y l f Y The roller.` 10visl provided Von its peripheralV surface with an irregular contourdelined by various lands and grooves simulating the surface roughness ofnatural rock land stone materials. The irregular contour characterizingthe peripheral surface of the roller 10 is adapted to be impressed uponthe base material or plastic sheet 14 and more particularly the uppersurface 15 thereof as the sheet of plastic material 14 passes in thedirection of the arrow between the rollers 10 and 11. Thus, the rollers10 and 11 are spaced slightly closer to each other than the thickness ofthe plastic material 14.

The plastic material 14 is preferably formed of a polystyrene plasticexpanded into a non-permeable multicellular mass, for example, ascharacterizes the trademarked product, Styrofoam, manufactured by theDow Chemical Company. Of course, other types of foamed plastic materials(for example, foamed cellulose acetate) may be employed so long as theyare characterized by a multi-open cellular construction and so long asthey are thermo-plastic to the extent that they will deform and remainin the deformed condition upon being subjected to a given pressure. i

It should be noted, however, that foamed plastic materials cannot beused which have the characteristic of springing bac to their originalshape upon removal of the pressure forming member. Thus, syntheticsponge cellulose products presently on the market are not satisfactoryfor purposes of the present invention.

After the polystyrene plastic sheet 14 has been forced through therotating rollers 10 and 11, the upper surface 15 thereof will be formedinto the irregular contour denoted by the numeral 16. It is apparentthat this irregular contour could equally well be formed by an embossingpunch or die although the roller apparatus method enables contouring thesurface of the plastic material continuously and conveniently over longlengths of panels or sheets thereof.

After formation of the simulated stone surface or roughened contour 16,a layer of colored adhesive material 17 is applied to the surface 16, asindicated by the numeral 17 in Figure 2. Preferably, an oil base paintis employed for this purpose which is characterized by 9 d. acolor upondrying similar to that of the surface coloring of stone or rock.Conventional oil base paint, because of its chemical composition, hasbeen found to satisfactorily adhere to the foarned plastic material 14aswell as provide a suitable base material for the final step ofapplying sand-like particles 18 (as shown in Figure 3) to most closelyapproximate and simulate natural stone or rock.

In this regard, before the paint 16 has dried and preferably immediatelyafter its application either by spraying or brushing, sand particles 18are blasted or otherwise deposited onto and into the paint, layer 17such that they become partially imbedded therein to co-,operate with thepaint and the cells of the plastic material 14` to simulate a rock-likesurface. As the paint 17 dries, the sand` particles Will becomerelatively firmly xed therein and in some instances partiallyk imbeddedin the cells of the plastic sheet 14 whereby an unusually similarappearance to natural rock is attained.

Although sand particles 18 are preferably employed, it is, of course,conceivable that synthetic particles or other equivalent material may beemployed of similar appearance and size to sand particles. However,because of the availability of sand particles and the relativelyeconomical cost involved, such materiall is preferred.

It will be appreciated that certain changes and modidations may be madein the materials employed and the steps of the present invention withoutdeparting-from the spirit and scope thereof as set forth in thefollowing claims.

What is claimed is:

1. The method of making a simulated stone product comprising the stepsof: subjecting an exterior portion of a foamed polystyrene plasticmaterial to a given pressure of an embossing member to effect theformation of an irregular contour in said exterior portion; forming alayer of an oil base paint coating over said exterior portion conformingto and retaining said irregular contour; and, depositing sand particleson said paint layer prior to the drying thereof.

2. The methodv of making a simulated stone product according to thesteps of claim 1, in Which said paint includes coloring mattersimulating upon drying the natural color of stone or rock.

3. The method of making la simulated stone product comprising the stepsof subjecting an exterior portion of an expanded polystyrene plasticmaterial to a given pressure of an embossing member to effect theformation of an irregular contour in said exterior portion; forming alayer of colored adhesive over said exterior portion conforming to andretaining said irregular contour; and depositing sand particles ontosaid colored adhesive layer prior to the drying thereof.

References Cited in the file of thispatent UNITED STATES PATENTS 459,066Glock Sept. 8, 1891 1,441,861 Lehon Jan. 9, 1923 1,574,890 Hofmann Mar.2, 1926 2,151,220 Mattes Mar. 21, 1939 2,618,901 Braun NOV. 25, 19522,663,527 Ioslyn Dec. 22, 1953 2,780,533 Hurst Feb. 5, 1957

1. THE METHOD OF MAKING A SIMULATED STONE PRODUCT COMPRISING THE STEPSOF: SUBJECTING AN EXTERIOR PORTION OF A FOAMED POLYSTYRENE PLASTICMATERIAL TO A GIVEN PRESSURE OF AN EMBOSSING MEMBER TO EFFECT THEINFORMATION OF AN IRREGULAR CONTOUR IN SAID EXTERIOR PORTION, FORMING ALAYER OF AN OIL BASE PAINT COATING OVER SAID EXTERIOR PORTION CONFORMINGTO AND RETAINING SAID IRREGULAR CONTOUR, AND, DEPOSITING SAND PARTICLESON SAID PAINT LAYER PRIOR TO THE DRYING THEREOF.